

($ in thousands)	March 31, 2021
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
AFS debt securities:
U.S. Treasury securities	$	841,711	$	328	$	(15,697)	$	826,342
U.S. government agency and U.S. government-sponsored enterprise debt securities	1,236,446		5,145		(47,586)		1,194,005
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities:
Commercial mortgage-backed securities	1,178,238		16,407		(25,254)		1,169,391
Residential mortgage-backed securities	2,271,645		17,026		(41,265)		2,247,406
Municipal securities	417,676		7,348		(4,959)		420,065
Non-agency mortgage-backed securities:
Commercial mortgage-backed securities	281,099		4,311		(4,383)		281,027
Residential mortgage-backed securities	525,560		1,599		(3,659)		523,500
Corporate debt securities	517,309		4,677		(25,343)		496,643
Foreign government bonds	278,100		320		(2,092)		276,328
Asset-backed securities	62,762		292		(14)		63,040
CLOs	294,000		—		(2,534)		291,466
Total AFS debt securities	$	7,904,546	$	57,453	$	(172,786)	$	7,789,213



($ in thousands)	December 31, 2020
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
AFS debt securities:
U.S. Treasury securities	$	50,310	$	451	$	—	$	50,761
U.S. government agency and U.S. government-sponsored enterprise debt securities	806,814		8,765		(1,260)		814,319
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities:
Commercial mortgage-backed securities	1,125,174		34,306		(5,710)		1,153,770
Residential mortgage-backed securities	1,634,553		27,952		(1,611)		1,660,894
Municipal securities	382,573		13,588		(88)		396,073
Non-agency mortgage-backed securities:
Commercial mortgage-backed securities	234,965		6,107		(1,230)		239,842
Residential mortgage-backed securities	288,520		1,761		(506)		289,775
Corporate debt securities	406,323		3,493		(3,848)		405,968
Foreign government bonds	183,828		163		(1,460)		182,531
Asset-backed securities	63,463		10		(242)		63,231
CLOs	294,000		—		(6,506)		287,494
Total AFS debt securities	$	5,470,523	$	96,596	$	(22,461)	$	5,544,658

As of March 31, 2021 and December 31, 2020, the amortized cost of AFS debt securities excluded accrued interest receivables of $22.9 million and $22.3 million, respectively, which are included in Other assets on the Consolidated Balance Sheet. For the Company’s accounting policy related to AFS debt securities’ accrued interest receivable, see Note 1 — Summary of Significant Accounting Policies — Allowance for Credit Losses on Available-for-Sale Debt Securities to the Consolidated Financial Statements in the Company’s 2020 Form 10-K.

The following tables present the fair value and the associated gross unrealized losses of the Company’s AFS debt securities, aggregated by investment category and the length of time that the securities have been in a continuous unrealized loss position as of March 31, 2021 and December 31, 2020.



($ in thousands)	March 31, 2021
	Less Than 12 Months				12 Months or More				Total
	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
AFS debt securities:
U.S. Treasury securities	$	775,801	$	(15,697)	$	—	$	—	$	775,801	$	(15,697)
U.S. government agency and U.S. government sponsored enterprise debt securities	954,894		(47,586)		—		—		954,894		(47,586)
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities:
Commercial mortgage-backed securities	615,193		(25,203)		3,474		(51)		618,667		(25,254)
Residential mortgage-backed securities	1,464,574		(41,264)		358		(1)		1,464,932		(41,265)
Municipal securities	199,225		(4,959)		—		—		199,225		(4,959)
Non-agency mortgage-backed securities:
Commercial mortgage-backed securities	114,971		(4,374)		15,578		(9)		130,549		(4,383)
Residential mortgage-backed securities	391,444		(3,659)		—		—		391,444		(3,659)
Corporate debt securities	347,934		(25,316)		9,974		(27)		357,908		(25,343)
Foreign government bonds	155,299		(2,092)		—		—		155,299		(2,092)
Asset-backed securities	11,904		(14)		—		—		11,904		(14)
CLOs	—		—		291,466		(2,534)		291,466		(2,534)
Total AFS debt securities	$	5,031,239	$	(170,164)	$	320,850	$	(2,622)	$	5,352,089	$	(172,786)



($ in thousands)	December 31, 2020
	Less Than 12 Months				12 Months or More				Total
	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
AFS debt securities:
U.S. Treasury securities	$	352,521	$	(1,260)	$	—	$	—	$	352,521	$	(1,260)

U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities:
Commercial mortgage-backed securities	292,596		(5,656)		3,543		(54)		296,139		(5,710)
Residential mortgage-backed securities	342,561		(1,611)		—		—		342,561		(1,611)
Municipal securities	24,529		(88)		—		—		24,529		(88)
Non-agency mortgage-backed securities:
Commercial mortgage-backed securities	58,738		(1,230)		7,920		—		66,658		(1,230)
Residential mortgage-backed securities	90,156		(506)		—		—		90,156		(506)
Corporate debt securities	251,674		(3,645)		9,798		(203)		261,472		(3,848)
Foreign government bonds	106,828		(1,460)		—		—		106,828		(1,460)
Asset-backed securities	—		—		34,104		(242)		34,104		(242)
CLOs	—		—		287,494		(6,506)		287,494		(6,506)
Total AFS debt securities	$	1,519,603	$	(15,456)	$	342,859	$	(7,005)	$	1,862,462	$	(22,461)

As of March 31, 2021, the Company had a total of 291 AFS debt securities in a gross unrealized loss position with no credit impairment that were comprised primarily of 112 U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities, 41 U.S. government agency and U.S. government sponsored enterprise debt securities and 26 corporate debt securities. In comparison, as of December 31, 2020, the Company had a total of 104 AFS debt securities in a gross unrealized loss position with no credit impairment that were comprised primarily of 46 U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities and 17 corporate debt securities.

Each reporting period, the Company assesses each AFS debt security that is in an unrealized loss position to determine whether the decline in fair value below the amortized cost basis resulted from a credit loss or other factors. For a discussion of the factors and criteria the Company uses in analyzing securities for impairment related to credit losses, see Note 1 — Summary of Significant Accounting Policies — Allowance for Credit Losses on Available-for-Sale Debt Securities to the Consolidated Financial Statements in the Company’s 2020 Form 10-K.

•U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities — The market value decline as of March 31, 2021 was primarily due to interest rate movement. Since these securities (issued by Fannie Mae, Ginnie Mae and Freddie Mac) are guaranteed or sponsored by agencies of the U.S. government, and the credit profiles are strong (rated Aaa, AA+ and AAA by Moody’s Investors Service (“Moody’s”), Standard and Poor's (“S&P”) and Fitch Ratings (“Fitch”), respectively), the Company expects to receive all contractual interest payments on-time, and believes the risk of credit losses on these securities is remote.

As these securities are guaranteed or sponsored by the U.S. government and the credit profiles are strong, the Company expects to receive all contractual interest payments on time, and believes the risk of credit losses on these securities is remote.

•Corporate debt securities — The market value decline as of March 31, 2021 was primarily due to interest rate movement and the widening in spreads. Since credit profiles of the securities are strong (rated BBB- or higher by Moody’s, S&P, Kroll Bond Rating Agency and Fitch), and the contractual payments from these bonds have been and are expected to be received on time, the Company believes that the risk of credit losses on these securities is remote.

The impact of the Coronavirus Disease 2019 (“COVID-19”) pandemic has been muted by the government’s aggressive monetary policy, including benchmark rate cuts, and various relief measures that contributed to the gradual and steady recovery of the market to pre-pandemic levels. Overall, the Company believes that the credit support levels of the AFS debt securities are strong and, based on current assessments and macroeconomic forecasts, expects that full contractual cash flows will be received even if near-term credit performance could possibly suffer from future unpredictable impacts of the COVID-19 pandemic.

As of March 31, 2021 and December 31, 2020, the Company had the intent to hold the AFS debt securities with unrealized losses through the anticipated recovery period and it was more-likely-than-not that the Company will not have to sell these securities before recovery of their amortized cost. The issuers of these securities have not, to the Company’s knowledge, established any cause for default on these securities. As a result, the Company expects to recover the entire amortized cost basis of these securities. Accordingly, there was no allowance for credit losses as of March 31, 2021 and December 31, 2020 provided against these securities. In addition, there was no provision for credit losses recognized for the three months ended March 31, 2021 and 2020.

The following table presents the contractual maturities of AFS debt securities as of March 31, 2021. Expected maturities will differ from contractual maturities on certain securities as the issuers and borrowers of the underlying collateral may have the right to call or prepay obligations with or without prepayment penalties.



($ in thousands)	Amortized Cost		Fair Value
Due within one year	$	1,403,404	$	1,347,808
Due after one year through five years	688,387		681,602
Due after five years through ten years	1,427,893		1,414,362
Due after ten years	4,384,862		4,345,441
Total AFS debt securities	$	7,904,546	$	7,789,213